OBJECTIVES: This study assessed the health risks for children exposed to phthalate through several pathways including house dust, surface wipes and hand wipes in child facilities and indoor playgrounds. METHODS: The indoor samples were collected from various children's facilities (40 playrooms, 42 daycare centers, 44 kindergartens, and 42 indoor-playgrounds) in both summer (Jul-Sep, 2007) and winter (Jan-Feb, 2008). Hazard index (HI) was estimated for the non-carcinogens and the examined phthalates were diethylhexyl phthalate (DEHP), diethyl phthalate (DEP), dibutyl-n-butyl phthalate (DnBP), and butylbenzyl phthalate (BBzP). The present study examined these four kinds of samples, i.e., indoor dust, surface wipes of product and hand wipes. RESULTS: Among the phthalates, the detection rates of DEHP were 98% in dust samples, 100% in surface wipe samples, and 95% in hand wipe samples. In this study, phthalate levels obtained from floor dust, product surface and children's hand wipe samples were similar to or slightly less compared to previous studies. The 50th and 95th percentile value of child-sensitive materials did not exceed 1 (HI) for all subjects in all facilities. CONCLUSIONS: For DEHP, DnBP and BBzP their detection rates through multi-routes were high and their risk based on health risk assessment was also observed to be acceptable. This study suggested that ingestion and dermal exposure could be the most important pathway of phthalates besides digestion through food.
2,4-Dinitrophenol ; Child ; Diethylhexyl Phthalate ; Digestion ; Dust ; Eating ; Floors and Floorcoverings ; Hand ; Humans ; Phthalic Acids ; Risk Assessment

As an effective antipyretic medicine,Indigo Naturalis has a long history of application in the field of Chinese medicine.The content of organics,mainly indigo and indirubin,is about 10%. However,the active ingredients and mechanism of its antipyretic effect have not yet been fully elucidated. In view of this,they were investigated in this study with the rectal temperature change as an indicator and 2,4-dinitrophenol-induced fever rats as subjects. The content of PGE2 and c AMP in the hypothalamus and the serum levels of TNF-α,IL-1β and IL-6 were determined by ELISA. Moreover,the plasma samples of fever rats were analyzed by metabonomics in combination with UPLC-Q-TOF-MS for the exploration of potential biomarkers and the discussion on the antipyretic mechanism of Indigo Naturalis and its active ingredients. The results showed that the rising trend of rectal temperature in rats was suppressed 0. 5 h after the treatment with Indigo Naturalis,organic matter,indigo or indirubin as compared with the rats of model group( P < 0. 05),among which Indigo Naturalis and organic matter had better antipyretic effect. ELISA results showed that organic matter and indigo can inhibit the expression of PGE2 and c AMP( P<0. 01),while Indigo Naturalis and organic matter were effective in curbing the increase in TNF-α( P<0. 05). A total of 21 endogenous metabolites were identified from the plasma samples of the Indigo Naturalis,organic matter,indigo and indirubin groups,which were mainly involved in glycerophospholipid metabolism.
2,4-Dinitrophenol ; Animals ; Antipyretics ; Drugs, Chinese Herbal ; Indigo Carmine ; Indigofera ; Rats

OBJECTIVETo evaluate the role of outer membrane protein (Omp) F-deficiency and active efflux in the accumulation of hydrophilic fluoroquinolones ciprofloxacin (CPLX) and lomefloxacin (LMLX) in resistant E. coli strains.

METHODSFluoroquinolone accumulation in bacteria and the effect of active efflux were measured by a fluorescence method. The outer membrane proteins of the bacteria were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). E. coli strains in this study included control strains JF701 and JF703 that are OmpC- or OmpF-deficient mutants of E. coli K-12, respectively, and the fluoroquinolone susceptible strain the fluoroquinolone susceptible strain of Escherichia coli (Ecs) and its in vitroselected resistant strains R2 and R256, and the clinical resistant isolates R5 and R6.

RESULTSThe steady-state accumulation concentration of each drug in Ecs appeared to be the same as in JF701, while in the OmpF-deficient strain JF703, it was 1/5 CPLX or 1/2 LMLX lower than that in JF701, but JF703 was still susceptible to fluoroquinolones. On the other hand, compared with susceptible strains, a 2- to 10-fold decrease in the accumulation of each drug was found in the resistant strains except R2, in which the accumulation was slightly higher than in JF703. After the addition of 2,4-dinitrophenol (DNP), accumulation of each drug increased, especially in resistant strains, indicating that the function of the active efflux (pump) system in these bacteria had been enhanced dramatically. Furthermore, both OmpF and OmpC in Ecs, OmpF-deficiency in R2 and R256 and OmpC-deficiency in R5 and R6 were observed.

CONCLUSIONThe decreased accumulation of hydrophilic fluoroquinolones in E. coli involved OmpF-deficiency and active efflux (pump), and the latter may be an important factor.

2,4-Dinitrophenol ; pharmacology ; Anti-Infective Agents ; metabolism ; pharmacology ; Ciprofloxacin ; metabolism ; pharmacology ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; metabolism ; Fluoroquinolones ; Porins ; physiology ; Quinolones ; metabolism ; pharmacology

Although trimethoprim-sulfamethoxazole (TMP-SXT) is considered the first-line therapy for Stenotrophomonas maltophilia infections, there is debate on the use of the bacteriostatic drug in serious infections, and recently, there has been an increasing occurrence of acquired resistance to TMP-SXT. In the present study, the effect of efflux pump inhibitors on the susceptibility of TMP-SXT and other antibiotics were investigated in S. maltophilia complex. The sul and/or dfrA genes were identified in only up to 27.8% of all 36 TMP-SXT-resistant S. maltophilia complex isolates. Thus, TMP-SXT resistance in S. maltophilia was not explained completely by the presence of sul and dfrA genes. Carbonyl cyanide-m-chlorophenylhydrazone (CCCP) decreased the minimum inhibitory concentration (MIC) of TMP-SXT by eight to 128 folds in all 14 isolates. In contrast, 2,4-dinitrophenol (DNP), phenyl-arginine-β-naphthylamide (PAβN), and reserpine did not reduce the MIC of TMP-SXT. In addition to TMP-SXT, slight decrease in MICs was observed for tigecycline and piperacillin/tazobactam by CCCP (by two folds) in one isolate. Although efflux pump may play a role in TMP-SXT resistance in S. maltophilia, inhibition of the efflux pump could be done by active proton pore.
2,4-Dinitrophenol ; Anti-Bacterial Agents ; Carbonyl Cyanide m-Chlorophenyl Hydrazone ; Korea* ; Microbial Sensitivity Tests ; Protons ; Reserpine ; Stenotrophomonas maltophilia* ; Stenotrophomonas* ; Thiram* ; Trimethoprim, Sulfamethoxazole Drug Combination*

To explore whether Cl- channel blockers interact with the ATP-sensitive K+ (KATP) channel, I have examined the effect of two common Cl- channel blockers on the KATP channel activity in isolated rat ventricular myocytes using patch clamp techniques. In inside-out patches, 4,4'-diisothio-cyanatostilbene-2,2'-disulfonic acid (DIDS) and niflumic acid applied to bath solution inhibited the KATP channel activity in a concentration-dependent manner with IC50 of 0.24 and 927 muM, respectively. The inhibitory action of DIDS was irreversible whereas that of niflumic acid was reversible. Furthermore, DIDS-induced block was not recovered despite exposure to ATP (1 mM). In cell-attached and inside-out patches, DIDS blocked the pinacidil- or 2,4-dinitrophenol (DNP)-induced KATP channel openings. In contrast, niflumic acid did not block the pinacidil-induced KATP channel openings in inside-out patches, but inhibited it in cell-attached patches. DIDS and niflumic acid produced additional block in the presence of ATP and did not affect current-voltage relationship and channel kinetics. All these results indicate that DIDS among Cl- channel blockers specifically blocks the cardiac KATP channel.
2,4-Dinitrophenol ; 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid ; Adenosine Triphosphate ; Animals ; Baths ; Inhibitory Concentration 50 ; Kinetics ; Muscle Cells ; Niflumic Acid ; Patch-Clamp Techniques ; Rats

AIMTo study the enhancement effect and mechanism of sodium N-[8-(2-hydroxybenzyl) amino] caprylate (SNAC--a kind of synthetic enhancer) to insulin (INS) solution in gastrointestine.

METHODSTo determine the enhancement effect of SNAC on INS absorption by oral administration to rats and mice; To study the enhancement mechanism of SNAC by three kinds of methods: Delivering SNAC and INS solution to different parts of rats' intestines, adding energy inhibitor 2,4-dinitrophenol (DNP) or P-glycoprotein (P-gp) inhibitor verapamil (Ver) into SNAC and INS solution.

RESULTSSNAC was shown to enhance the gastrointestinal absorption of INS, the intensity of absorption enhancement corresponded to the doses of SNAC. The enhancement of SNAC to INS in different parts of the rat intestine was different (jejunum > colon > ileum). The effect of SNAC on INS absorption increased accordingly.

CONCLUSIONThe enhancement of SNAC to INS absorption presented dose dependence on SNAC; the absorption process needed energy and related to P-gp efflux.

2,4-Dinitrophenol ; pharmacology ; Animals ; Caprylates ; administration & dosage ; pharmacology ; Colon ; metabolism ; Dose-Response Relationship, Drug ; Ileum ; metabolism ; Insulin ; metabolism ; Intestinal Absorption ; drug effects ; Jejunum ; metabolism ; Male ; Mice ; Rats ; Rats, Sprague-Dawley ; Verapamil ; pharmacology

2,4-dinitrophenol (DNP), an organic compound which frequently used in industry, is considered to have high toxicity. This study aimed to investigate the early changes of lymphocyte subpopulations in patients with occupational 2,4-DNP poisoning. Totally 9 patients with acute occupational 2,4-DNP poisoning and 30 healthy volunteers as control were enrolled. The patients received immediately comprehensive supportive treatments, including large-dose glucocorticoid and repeated hemoperfusion (HP). The ratio of CD4+/CD8+ T cells were significantly higher in patients upon admission compared to healthy controls (P < 0.01); however, counts of total lymphocytes, CD3+, CD3+CD4+, CD3+CD8+, B (CD19+), and natural killer (NK) cells (CD16+CD56+) were significantly reduced (all P < 0.001). The NK cell count was negatively correlated with initial plasma 2,4-DNP concentration (r = -0.750, P = 0.026). Thus, acute occupational 2,4-DNP poisoning was accompanied by immediate complex immune cell reactions, especially NK cells might play important role in severe 2,4-DNP poisoning.
2,4-Dinitrophenol ; poisoning ; toxicity ; Adult ; China ; Coloring Agents ; poisoning ; toxicity ; Female ; Humans ; Killer Cells, Natural ; drug effects ; Lymphocyte Subsets ; drug effects ; Male ; Middle Aged ; Occupational Diseases ; chemically induced ; T-Lymphocytes ; drug effects